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The origin of the phase separation in partially deuterated $κ$-(ET)$_2$Cu[N(CN)$_2$]Br studied by infrared magneto-optical imaging spectroscopy

T. Nishi·S. Kimura·T. Takahashi·T. Ito·H. J. Im·Y. S. Kwon·K. Miyagawa·H. Taniguchi·A. Kawamoto·K. Kanoda
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Abstract

The direct observation of the phase separation between the metallic and insulating states of 75 %-deuterated $κ$-(ET)$_2$Cu[N(CN)$_2$]Br ($d33$) using infrared magneto-optical imaging spectroscopy is reported, as well as the associated temperature, cooling rate, and magnetic field dependencies of the separation. The distribution of the center of spectral weight ($< ω>$) of $d33$ did not change under any of the conditions in which data were taken and was wider than that of the non-deuterated material. This result indicates that the inhomogenity of the sample itself is important as part of the origin of the metal - insulator phase separation.

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T. Nishi, S. Kimura, T. Takahashi, T. Ito, H. J. Im, Y. S. Kwon, K. Miyagawa, H. Taniguchi, A. Kawamoto, K. Kanoda. 2005-01-10. The origin of the phase separation in partially deuterated $κ$-(ET)$_2$Cu[N(CN)$_2$]Br studied by infrared magneto-optical imaging spectroscopy. https://doi.org/10.1016/j.ssc.2005.01.026

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